Analogy between the Schwarzschild solution in a noncommutative gauge theory and the Reissner-Nordström metric

Abstract

We study modifications of the Schwarzschild solution within the noncommutative gauge theory of gravity. In the present analysis, the deformed solutions are obtained by solving the field equations perturbatively, up to the second order in the noncommutativity parameter Θ, for both exterior and interior solutions of the equations of motion for eμa(x). Remarkably, we find that this new noncommutative solution is analogous to the Reissner-Nordström solution in the ordinary spacetime, in which the square of the electric charge is replaced by the square of the noncommutativity parameter, but with opposite sign. This amounts to the noncommutative Schwarzschild radius rNCS becoming larger than the usual radius rS=2M, instead of smaller as it happens to the Reissner-Nordström radius rRN, implying that rNCS>rS>rRN. An intuitive interpretation of this result is mentioned.